Considered the most important baroque monument in Portugal, the Palace of Mafra was built by Dom Joao V. It has a set of six historical organs in the Basilica, a Conventual Nucleus, with a hospital of the time and an extraordinary library of the 18th century, with 83 meters and about 38000 volumes, which include books of the XVI, XVII and XVIII centuries, many of them rare. It is a rich and precious library in a space of fascination, by far the most important royal monastic library of the eighteenth century in Portugal.